Effect Of Mirthful Laughter On Vascular Function

In contrast to the well-established scientific evidence linking negative emotional states (e.g., depression, anxiety, or anger) to increased risk for cardiovascular disease, much less is known about the association between positive emotional states (e.g., laughter, happiness) and cardiovascular health. We determined the effects of mirthful laughter, elicited by watching comic movies, on endothelial function and central artery compliance. Seventeen apparently healthy adults (23 to 42 years of age) watched 30 minutes of a comedy or a documentary (control) on separate days (crossover design). Heart rate and blood pressure increased significantly while watching the comedy, whereas no such changes were seen while watching the documentary. Ischemia-induced brachial artery flow-mediated vasodilation (by B-mode ultrasound imaging) increased significantly after watching the comedy (17%) and decreased with watching the documentary (-15%). Carotid arterial compliance (by simultaneous application of ultrasound imaging and applanation tonometry) increased (10%) significantly immediately after watching the comedy and returned to baseline 24 hours after the watching, whereas it did not change significantly throughout the documentary condition. Comedy-induced changes in arterial compliance were significantly associated with baseline flow-mediated dilation (r = 0.63). These results suggest that mirthful laughter elicited by comic movies induces beneficial impact on vascular function. (C) 2010 Elsevier Inc. All rights reserved. (Am J Cardiol 2010;106:856-859)Kinesiology and Health Educatio

Ab initio study of 2p-core level x-ray photoemission spectra in ferromagnetic transition metals

We study the 2p-core level x-ray photoemission spectra in ferromagnetic transition metals, Fe, Co, and Ni using a recently developed ab initio method.The excited final states are set up by distributing electrons on the one-electron states calculated under the fully screened potential in the presence of the core hole. We evaluate the overlap between these excited states and the ground state by using one-electron wave functions, and obtain the spectral curves as a function of binding energy. The calculated spectra reproduce well the observed spectra displaying interesting dependence on the element and on the spin of the removed core electron. The origin of the spectral shapes is elucidated in terms of the one-electron states screening the core hole. The magnetic splitting of the threshold energy is also estimated by using the coherent potential approximation within the fully screened potential approximation. It decreases more rapidly than the local spin moment with moving from Fe to Ni. It is estimated to be almost zero for Ni despite the definite local moment about 0.6\mu_B, in agreement with the experiment.Comment: 10 pages, 7 figure

An ab initio study of 3s core-level x-ray photoemission spectra in transition metals

We calculate the $3s$- and $4s$-core-level x-ray photoemission spectroscopy (XPS) spectra in the ferromagnetic and nonmagnetic transition metals by developing an \emph{ab initio} method. We obtain the spectra exhibiting the characteristic shapes as a function of binding energy in good agreement with experimental observations. The spectral shapes are strikingly different between the majority spin channel and the minority spin channel for ferromagnetic metals Ni, Co, and Fe, that is, large intensities appear in the higher binding energy side of the main peak (satellite) in the majority spin channel. Such satellite or shoulder intensities are also obtained for nonmagnetic metals V and Ru. These behaviors are elucidated in terms of the change of the one-electron states induced by the core-hole potential.Comment: 11 pages, 12 figures, to appear in Phys. Rev.

High Ecliptic Latitude Survey for Small Main-Belt Asteroids

Main-belt asteroids have been continuously colliding with one another since they were formed. Its size distribution is primarily determined by the size dependence of asteroid strength against catastrophic impacts. The strength scaling law as a function of body size could depend on collision velocity, but the relationship remains unknown especially under hypervelocity collisions comparable to 10 km/sec. We present a wide-field imaging survey at ecliptic latitude of around 25 deg for investigating the size distribution of small main-belt asteroids which have highly inclined orbits. The analysis technique allowing for efficient asteroid detections and high-accuracy photometric measurements provide sufficient sample data to estimate the size distribution of sub-km asteroids with inclinations larger than 14 deg. The best-fit power-law slopes of the cumulative size distribution is 1.25 +/- 0.03 in the diameter range of 0.6-1.0 km and 1.84 +/- 0.27 in 1.0-3.0 km. We provide a simple size distribution model that takes into consideration the oscillations of the power-law slope due to the transition from the gravity-scaled regime to the strength-scaled regime. We find that the high-inclination population has a shallow slope of the primary components of the size distribution compared to the low-inclination populations. The asteroid population exposed to hypervelocity impacts undergoes collisional processes that large bodies have a higher disruptive strength and longer life-span relative to tiny bodies than the ecliptic asteroids.Comment: 24 pages, 9 figures, accepted for publication in A